Recent advances in the telecommunications and electronics industry, and, in particular, improvements in digital compression techniques, networking, and hard drive capacities have led to growth in new digital services to a user's home. For example, such advances have provided hundreds of cable television channels to users by compressing digital data and digital video, transmitting the compressed digital signals over conventional coaxial cable television channels, and then decompressing the signals in the user's receiver. One application for these technologies that has received considerable attention recently includes video-on-demand (VOD) systems where a user may communicate with a service operator to request media content and the requested content is routed to the user's home for enjoyment. The service operator typically obtains the content from an upstream content provider, such as a content owner, distributor, and the like.
However, to protect such content from unauthorized use, service operators, content providers, owners, and so forth, may employ a service known as conditional access. Conditional access enables a provider to restrict selected content to selected users. This may be achieved, for example by encrypting the content. A content provider, content owner, or the like, may wish to encrypt the content as early in a distribution stream as possible to protect the content from piracy.
However, today's users may want to perform various actions on the content, including fast forwarding through a portion of the content, fast reversing, and the like. Such “trick plays” are typically managed by generating additional file information from the content. Creation of these trick play files may be difficult when the content is encrypted. Therefore, it is with respect to these considerations and others that the present invention has been made.